A system is considered in which a security sensor is installed in a room serving as a monitoring area and when the security sensor detects an abnormality, a mobile robot including a camera is rushed to a location where the abnormality occurs. When the security sensor detects an abnormality in such a system, the mobile robot captures an image of the surroundings with a camera. The captured video is transmitted to a surveillance staff located away from the scene through a network line or the like. Thus, despite being in a place away from the scene, the surveillance staff can check the condition of the scene where the abnormality is detected by checking the video captured by the camera.